JP4808807B2 - Method and apparatus for repairing a well by hydroforming a cylindrical metal patch, and a patch for this purpose - Google Patents

Abstract

A method of patching a well or a pipe by hydroforming a tubular metal patch. A tool provided with a pair of inflatable packers is inserted inside the patch. The pair of inflatable packers are axially spaced apart from each other by a distance that is substantially equal to the length of the patch. The tool is positioned inside the patch so that the packers are in register with the end portions of the patch. The assembly of the tool and the patch is axially inserted inside the well or the pipe, and positioned in register with the zone for patching. The packers are inflated to a high pressure, sufficient for radially expanding the end portions of the patch and pressing them in a leak-tight manner against the wall of the well or the pipe. The packers are subsequently deflated and the tool is withdrawn. The method is applicable to the oil industry.

Description

The present invention relates to a method and apparatus for repairing wells and pipes, such as casings, where there is a site that needs to be sealed, particularly for repair and / or stopper purposes.
The invention is more particularly but not necessarily applied when producing water or oil.

  In the following description, the present invention is described as an example of producing oil.

A casing is comprised by the metal pipe which lines the inside of an oil well over a long distance.
As a guide, this length can range, for example, from 2000 meters (m) to 4500 m. The inner diameter is in the range from 120 mm to 200 mm.

At the bottom, the casing is perforated, where it passes through one or more deposits so that oil and gaseous hydrocarbons can penetrate the well.
At the top end of the well there is a wellhead with various systems, especially for protection, suspension and sealing purposes.

  Over a long distance at the top of the well, e.g. in the range of 1500 m to 4000 m, the casing is for operating pipes and wells such as temporary closures (packers) and safety valves in its interior. It is equipped with a completed device consisting of various devices used for

  Over time, especially when parts of the casing walls have deteriorated, for example due to unexpectedly early wear and / or cracking, and particularly when the deposits in the area are depleted and undesirable fluids (especially water and When there is a need to stop holes that allow oil to pass through, there is a need for a leak seal on a part of the casing wall. Can happen.

  In order to provide leakage protection, the part is treated from the inside by being internally coated with a protective material, in particular a composite based on cement, gel or polymerisable resin.

To perform this procedure, one of two different techniques can be implemented:
The finished device is first lifted and then directly accesses the part of the casing to be treated;
• Or the tools and materials used for embedding pass through the finished device.

  The first technique is time consuming and expensive, and can lead to difficult operations. This is particularly because it is necessary to keep the well completely unusable before any action is taken.

  The second technique is complex and expensive and can only be used in the case of a limited number of configurations. This is due to the following reason. That is, the completed device generally has a much smaller diameter than the bottom area of the casing where the site for treatment is located.

  The present invention seeks to alleviate these disadvantages by proposing a method and apparatus that allows the bottom area of the casing to be lined through a smaller diameter finished device.

  The present invention applies not only to the casings described above, but also to any underground excavation wells and any optionally embedded pipes, so the description and the following claims line the wells or pipes. Refers to. Here, the pipe may be constituted by a casing, or any other duct, which may be vertical, horizontal or diagonal.

The present invention provides a method for repairing wells or pipes, such as casings, which have parts that need to be treated, in particular repaired and / or plugged.
According to the present invention, the method performs hydroforming of a tubular metal patch whose initial diameter is much smaller than the diameter of the well or pipe and consists of the following steps:
Insert a tool with a mandrel axially into the patch, where the mandrel is fitted with two inflatable packers, which expand radially by the action of internal fluid pressure These two packers are axially separated from each other by a distance substantially equal to or slightly shorter than the length of the patch;
Placing the tool in the patch so that the packer matches the edge of the patch;
Inserting an assembly of tools and patches in the axial direction and positioning the assembly to coincide with the area to be repaired;
Inflating the packer at high pressure, sufficient to cause the two ends of the patch to expand radially and be pressed against leaking against the inner wall of the well or pipe; and • Shrink the packer and remove the tool from the well or pipe.

  The following will be understood. That is, in some cases, the diameter of the assembly comprised of the tool (with the unexpanded packer) and the patch carried thereby is smaller than the diameter of the finished device, and the area located beyond the finished device It is possible to pass through the finished device to treat.

Conversely, once the area has been repaired, the contracted tool can be pulled through the finished device in the opposite direction.
According to one possible additional feature for carrying out the method, after the packer has contracted, at least partly, the two ends of the patch are against the inner wall of the well or pipe. For the purpose of pressing so as not to cause leakage, the central part of the patch located between the two ends is also brought into radial expansion by hydroforming, so that the second fluid in the pressurized state is Guided into the patch between the two packers, the expansion pressure of the packer is substantially higher than the pressure of the second fluid.

  The packer inflation pressure is naturally assumed to be higher than the pressure of the second fluid that causes the central portion of the patch to expand by hydroforming. To this end, it is sufficient to mechanically reinforce the end of the patch, exemplified by increasing the wall thickness or adding a ring that acts as a hoop.

Therefore, the radial expansion at these ends requires that the applied pressure be considerably higher than the radial expansion at the central portion of the patch.
This method is preferably performed in multiple stages.

Each stage consists of two consecutive stages.
In the first stage, the end is partially radially expanded so that a defined increase in diameter at the end is obtained by expanding the packer to a predetermined pressure that directly affects the desired increase in diameter. Can be extended to In the second stage, the rest of the patch is expanded radially, i.e. its central part, by hydroforming with a relatively small value of pressure selected to obtain a predetermined increase in diameter. Is expanded.

This operation is repeated one or more times until the desired expanded diameter in the central portion of the patch is obtained.
Finally, the end is subjected to final expansion and as a result it is pressed tightly so as not to leak against the well or pipe wall.

  This movement of the continuous stage makes it possible to give the patch a shape that is initially cylindrical or substantially cylindrical; otherwise its central portion has a convex raised or “barrel” shape Or, conversely, there is a risk that an edge effect will result in a concave “hourglass” shape.

  The number of stages to be executed naturally depends on the desired expansion factor. The number of stages increases with increasing desired expansion factor.

  At each stage, the pressure difference between the fluid to inflate the end packer and the hydroforming fluid allows the hydroforming fluid to be confined within the patch between the two packers.

  According to other possible additional features, the packer is slightly inflated once the tool has been placed inside the patch. The packer is then end-mounted so that the tool is fixed against the patch by friction so that the two elements temporarily form an integrated assembly that is easy to handle and install in place. The inner wall is pressed by a certain amount of pressing.

  According to another feature of the method, one or more sensors are placed at appropriate locations in the area in addition to or for the purpose of repairing or plugging the wall area. For this purpose, prior to work, the sensor is fixed to the wall outside the wall in the central part of the patch.

  Therefore, at the end of the work, the sensor is placed in an annulus between the central part of the patch and the wall of the well or pipe, so that the sensor protects any tool that can pass through the patch in future well management work .

  The device provided for repairing wells or pipes, such as casings, provided by the present invention for treatment, in particular for repair and / or in the part for stopcocks, has an initial diameter greater than the diameter of the well or pipe. Is a device for hydroforming a substantially small cylindrical metal patch.

  This device is characterized by the following facts. First, it comprises a tool suitable for axial insertion inside the patch, the tool comprising a mandrel having two inflatable packers thereon, the packer acting on the fluid pressure inside Can expand radially. The two packers are axially separated from each other by a distance that is substantially the same or slightly shorter than the length of the patch, and further have a diameter that is less than or equal to the inner diameter of the patch in a deflated state. The tool is also configured to be placed inside the patch so that the packer matches the edge of the patch. Second, after the assembly of the tool and patch is inserted into the well or pipe and the assembly is positioned to match the area to be repaired, the two ends of the patch are Fluid pressure means are provided for inflating the packer at a high pressure sufficient to expand radially in order to prevent leakage to the inner wall of the pipe.

Further, according to certain features of the device, the following are advantageous, but are not limited to:
The tool comprises an axial tube suitable for being selectively connected to a high pressure fluid pressure source or a low pressure source, the tube having supply and suction holes that open into the packer Further: the tool has an additional tube or channel suitable for being selectively connected to a high pressure fluid pressure source and has a supply hole that opens between the packers to the outside of the tool mandrel .

The present invention further provides a cylindrical metal patch for use with an apparatus having the above characteristics.
According to the advantageous features that this patch can take:
-Its end is mechanically reinforced. And their thickness is greater than the thickness of the central part of the patch;
It acts as a chisel and is reinforced at its end by an outer ring fitted onto the wall of the patch;
The end is provided with a jacket made of natural or synthetic rubber, suitable for improving the sealing performance when in contact with the inner wall of a well or pipe;
-The jacket is made of an inflatable material suitable for expansion when in contact with liquids, especially water or oil. ;
The patch has a longitudinally folded wall that promotes radial expansion of the patch by unfolding its relief by the effect of internal pressure;
The patch is used to position one or more sensors and comprises at least one sensor fixed to the central part outside the wall of the patch; Is housed.

FIG. 2 is a highly schematic axial cross-sectional view of a portion of an oil well before repairing a damaged area. 1 is a schematic axial sectional view of a tool constituting an apparatus according to the present invention. FIG. 2 is a schematic axial cross-sectional view of a cylindrical metal tubular patch for repairing a damaged region of a well. FIG. 3 is a detailed view of a striped portion referred to by W1 in FIG. FIG. 4 is a detailed view of a striped portion referred to by W2 in FIG. 3. FIG. 4 is a perspective view of a tool and a patch that receives the tool in the axial direction as indicated by arrow Q and in which the tool is fitted. It is an axial sectional view showing the state where the assembly of the tool and the patch is arranged at the position to be repaired inside the casing. FIG. 8 is a view similar to FIG. 7 showing various successive stages of the repair operation. FIG. 8 is a view similar to FIG. 7 showing various successive stages of the repair operation. FIG. 8 is a view similar to FIG. 7 showing various successive stages of the repair operation. FIG. 8 is a view similar to FIG. 7 showing various successive stages of the repair operation. FIG. 8 is a view similar to FIG. 7 showing various successive stages of the repair operation. FIG. 8 is a view similar to FIG. 7 showing various successive stages of the repair operation. FIG. 8 is a view similar to FIG. 7 showing various successive stages of the repair operation. FIG. 5 is a highly schematic axial cross-sectional view of a portion of an oil well after repairing a damaged area. It is a perspective view which shows the modification of the patch which has the wall folded. FIG. 6 is a cross-sectional view through the wall of the patch in the process of radial expansion occurring. FIG. 6 is a cross-sectional view through the wall of the patch in the process of radial expansion occurring. FIG. 6 is a cross-sectional view through the wall of the patch in the process of radial expansion occurring. It is a perspective view which shows the state before radial expansion is performed in the patch to which the sensor is attached. It is a perspective view which shows the state after radial expansion was performed in the patch to which the sensor was attached. It is a front view which shows the state similar to FIG. 11, and the patch is shown by the axial direction cross section inside a casing. It is a front view which shows the state similar to FIG. 11A, and the patch is shown by the axial direction cross section inside a casing. It is a perspective view which shows the modification of a patch, The setback part which accommodates a sensor is provided in the wall. FIG. 14 is an axial sectional view showing (enlarged) a modification of FIG. 13. FIG. 14 is a cross-sectional view in the transverse axis direction (enlarged) showing a modification of FIG. 13.

Other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings.
FIG. 1 shows a part of an oil drilling well lined by a casing C and having a cylindrical wall about the vertical XX ′ axis. The portion Z of the casing has a plurality of holes p from which water is generated and is desired to be plugged with a patch.

Code EC shows the complete device is held in place by an annular centering member A, its internal diameter d is significantly smaller than the diameter D ₀ of the casing.
By way of example, the diameter d is about 100 mm, while the diameter D ₀ is about 155 mm.

  FIG. 8 shows the same part of the well after the patch 4 has been placed in the part Z, so that this region is not leaked and the cylindrical metal wall 40 is The hole p is separated from the inside of the well by placing it in between.

In order to avoid interfering with the work in the well, the wall so that the completed device can reach the bottom of the well after treatment with a tool that could pass through the completed device of diameter d It is important that the inner diameter D of each is not less than d.
As will be described later, the present invention facilitates this.

  The device according to the invention shown in FIGS. 2 to 6 comprises a tubular tool 1, which consists essentially of a cylindrical mandrel 2 in the XX ′ axial direction, which mandrel is made of steel, for example. Surrounded by a pair of inflatable packers 3 that are also cylindrical, each packer in the form of a diaphragm made of a flexible and elastic material that can withstand pressure and corrosion, such as rubber or elastomer Has a wall.

The two packers 3 are held by a mandrel 2 having the same axial center, and are arranged at a predetermined distance in the axial direction.
The diaphragm constituting each packer is fixed in a sealed state to the end members 30 and 30 'at the ends thereof. One of the end members is then movable in the axial direction to accommodate the decrease in packer length associated with the radial expansion of the packer and conversely the increase in its length due to contraction.

  In the embodiment shown, it is the outer end member 30 ′ (top and bottom) that is movable, and the inner end member 30 is fixed to the mandrel 2. Of course, this arrangement is not an essential configuration, and in particular, the arrangement may be reversed.

At the free end, the mandrel has a cap 62, which serves as an abutment for the bottom end member 30 '.
At its opposite end, the ring 20 that secures to the mandrel forms an abutment for the top end member 30 '.

The mandrel has an axial flow path 6 for connection to a high pressure fluid source, which opens to the inside of each packer 3 through a radially oriented hole or holes 60.
Similarly, the mandrel 2 has another axial channel 7 for connection to a high pressure fluid source. The flow path 7 opens outward in the central region of the mandrel 2 through a hole or a plurality of holes 70 facing in the radial direction.

  These connections are made through suitable distribution valves that can be placed on top of the well, such as a high pressure fluid source. These valves (not shown) provide a selective and individual connection of flow paths 6 and 7 to a variable and controlled high pressure fluid source or vice versa.

The flow path 7 opens outside the mandrel 2 between the two inflatable packers 3 via a radial hole 70.
The tool 1 with its inflatable packer 3 has the same structure as a double inflatable sealing device of the kind commonly used in the petroleum industry.

The patch 4 used for repair purposes is made of metal (preferably steel) and includes a cylindrical tube having a relatively small thickness.
Its length substantially corresponds to the length of the tool, and its inner diameter is larger than the inner diameter of the tool 1 and the packer 3.

Therefore, as represented by the arrow Q in FIG. 6, the tool 1 can be fitted axially inside the tubular patch 4.
After being engaged, each packer 3 coincides with one position of the two ends 5 of the patch 4. These ends 5 are mechanically reinforced so that their resistance to radial expansion is significantly greater than that of the central portion 40 of the patch. More precisely, and as can be seen from FIG. 5, the wall of the patch in this region, indicated by reference numeral 41, is surrounded by a cylindrical metal ring 51, thereby increasing the total thickness of the wall.

These rings, acting as a chisel, considerably reinforce the mechanical strength of the wall in the patch end region.
In addition, the ring 51 has a sealing coating 52 on its outer side.

  By way of example, the coating comprises an annular layer of flexible and elastic material (e.g. elastomer or rubber), preferably with circumferential grooves between the embossed solid parts. It is sawtooth shaped so that each of these portions can be appropriately deformed when the end 5 is radially expanded and pressed against the casing.

In one variation, this coating layer could be replaced by a series of adjacent O-rings housed in grooves formed around ring 51.
As a material for making a coating or O-ring, a material that is suitable for expanding when in contact with liquids, liquids present in wells (especially water, mud, or oil) to further improve the sealability It is advantageous to use

The material having such characteristics is referred to in the patent document US 2004 / 0261990A1 by way of example, and may be referred to as necessary.
After the tools are engaged and properly placed in the patch 4, the packer 3 is slightly inflated by supplying medium pressure fluid through the channels 6 and holes 61. Here, this pressure is sufficient to hold the tool 1 by friction against the patch 4.

  Thus, these two elements form an integral assembly that is suitable for being inserted into the well and moving along the well for treatment. For this purpose, the assembly is suspended on a well-known type of hollow rod of the kind used for installing and moving mounting and guiding members, for example ordinary packers. Supply of pressurized liquid (not shown) is performed through the interior of the hanging rod.

It is also possible to use a tool that is provided with an electric pump that is suspended from an electric wire and that supplies a pressurized liquid.
The outer diameter of the assembly comprising the tool and the packer is selected to be smaller than the inner diameter d of the completion device EC so that the assembly can pass axially along the completion device.

The length of the assembly is selected to be slightly longer than the length of the area 8 to be treated, for example a few meters longer.
FIG. 7 shows the assembly being lowered through the completion device EC (arrow F) towards the zone Z with the holes to be repaired.

Once a position corresponding to this region is reached, the assembly remains stationary, as shown in FIG. 7A.
Then, the high-pressure liquid LHP is supplied to each of the packers 3 that can expand through the flow path 6 (arrow I) and the hole 6 (arrow i). This pressure value is chosen to be sufficient to expand the packer in the radial direction with the patch end 5 against which the packer presses.

This situation is shown in FIG. 7B.
When the increase in the diameter of the end 5 reaches a predetermined value, but the diameter remains below D ₀ , it is between the two inflatable packers 3 via the flow path 7 and the hole 70 (arrow j). A second high-pressure fluid lhp is supplied inside the patch 4. During this operation, in each inflatable packer 3, the liquid LHP is maintained at a high pressure.

The pressure of the second fluid lhp is sufficient to radially expand the central portion 40 of the patch whose walls are not reinforced, but is sufficiently lower than the pressure of the first fluid LHP.
The pressure difference, for example about 5 megapascals (MPa) or 50 bar, is selected sufficiently to prevent the undesired outflow of fluid lhp to the outside of the patch between the outer wall of the packer and the inner wall of the patch. .

Thus, the central portion 40 of the patch is radially expanded by hydroforming.
As shown in FIG. 7B1, the operation is stopped when its diameter reaches some predetermined diameter that is less than the maximum diameter of the end 5.

These two steps are repeated one or more times until the central portion 40 reaches the desired diameter. Thereafter, to seal presses the end portion against the inner wall of the casing C of the diameter D _0, packers are again inflated under high pressure.

The pressure of each liquid may be controlled so that the desired deformation is obtained for the end 5 and the central portion 40.
Of course, the radial expansion in each part of the patch automatically leads to a reduction in the wall thickness of those parts.

FIG. 7C shows an intermediate stage corresponding to the end 5 when in contact with the inner wall of the casing C. FIG.
As shown in FIG. 7D, the end portion 5 finally has a “tulip” shape, and its cylindrical portion presses closely and securely against the inner wall of the casing 3 so as not to leak.

  Thereafter, the packer 3 contracts to return to the original cylindrical shape due to the decrease in pressure, and therefore through the hole 60 (arrow i ′) and the channel 6 (arrow I ′) as shown in FIG. 7E. Liquid is allowed to flow out. Then, the liquid lhp confined between the packers 3 expanded inside the patch can naturally flow out to the well.

As shown in FIG. 7E1, the tool can then be withdrawn from the well (arrow F ′) by passing back through the completed device EC.
At this time, the configuration shown in FIG. 8 in which the region Z is lined with the tubular metal patch 4 that is expanded and fixed to the casing C is maintained.

Due to the leak-free connection between the end 5 and the wall of the casing, the hole p is completely separated and does not harm the work of the well.
The minimum diameter D of the patch 4 is larger than the diameter d of the finished device EC. As a result, the patch does not interfere with the work of the well. It may be advantageous to limit the expansion of the central portion 40 such that a relatively large angular space exists around the central portion 40. This space can be used, for example, to receive a specific device, such as a sensor, as described below.

The patch 8 shown in FIGS. 9 and 10 has a wall that is folded longitudinally, whereas its wall is usually cylindrical.
This folding is done through the entire length of the patch.

As in the above embodiment, the end 81 is reinforced compared to the central portion 80, and the end 81 is covered with a sealing coating.
As can be seen from FIG. 10, the wall of the patch has undulations 9 which are somewhat in the shape of “daisies flowers”.

  These folds are located outside the cylindrical envelope 90 and the tool packer used has a diameter equal to or smaller than the envelope diameter in the contracted state so that it can be fitted inside the patch. Of course you must have.

This folded shape allows the central portion 8 to be relatively greatly expanded.
Due to the effect of the pressure of the internal fluid lhp, the undulations 9a of the central portion 8a are initially observed so that the wall gradually develops in a “rounded shape” (FIG. 10A) and eventually becomes cylindrical. Thereafter, it is observed that the cylindrical shape is expanded (reference numeral 9b) while maintaining its cylindrical shape (reference numeral 9'a) (FIG. 10B).

After the end of expansion, the central portion 80 of the patch is accurately cylindrical with a constant diameter throughout its length.
Its end is also cylindrical and has a larger diameter.

A given tool may be used many times to install multiple patches in a single or different well.
The patch may be installed through the already installed patch.

  The nature of the metal used and its mechanical characteristics, in particular its ductility, as well as its wall thickness, are naturally selected depending on the degree of stress applied to the patch, in particular the stress required for radial expansion. Similarly, the fluid values used are suitable for these constraints.

Purely by way of example, one of the possible ranges for the dimensions of the patch according to the invention is given as follows.
The length of the center part 40: It exists in the range of 2m-12m, for example, 10m.

The length of the edge part 5: It exists in the range of 0.3m-1m, for example, 0.5m.
Diameter before expansion: in the range of 80 mm to 120 mm (for example, 100 mm).
Diameter after completion of expansion: in the range of 100 mm to 150 mm for the central portion 40 (eg 130 mm) and in the range of 120 mm to 180 mm at the end 5 (eg 155 mm).

  In the petroleum industry, it is often necessary to place a sensor, such as a temperature sensor, a pressure sensor, or a sensor for detecting the pressure of a gas or other predetermined substance, in the well and near its wall. Once these sensors are installed, they need to be protected so that they are protected from tools and other elements that can pass through the well.

The present invention provides a simple and reliable way to install this type of sensor and allows the sensor to be completely separated in the well once installed.
FIG. 11 shows a patch 4 in which a cylindrical portion 40 carries a sensor 100; the sensor may be cylindrical in shape and have a diameter that is much smaller than the diameter of the patch. The sensor is disposed longitudinally along the patch bus and is adjacent to its central portion 40.

Appropriate stop means, such as a pair of elastic annular straps Ll and L2, serve to hold the sensor in place.
These straps do not prevent radial expansion of the central portion 40 (FIG. 11A).

The patch 4 is installed as described above.
As can be seen by looking at FIG. 12A, after the patch 4 has been installed, the sensor 100 is the surrounding space completely surrounding the central portion 40 inside the casing C, and is expanded by the expanded portion 5. The two ends are separated into a sealed space.

Of course, multiple sensors could be placed around the patch before the patch is installed.
In the variant shown in FIGS. 13-15, the central part has a small longitudinal recess 400, which is formed by pressing and serves to initially accommodate the sensor. With this configuration, the sensor does not project outside the cylindrical normal of the patch, and therefore when the tool and patch assembly is lowered under the well, especially when passing through the finished device. Avoids the risk of contact and damage.

While the patch is expanding, the setback of the wall 400 unfolds like the folded patch relief shown in FIGS. 9 and 10, and the central portion 40 becomes cylindrical.
Of course, if the preparation for installing a plurality of sensors is made, the wall may be provided with a plurality of setbacks each having a shape suitable for receiving the sensors.

Claims (16)

A method of repairing a well or pipe, for example a casing (C), comprising:
The well or pipe has a part which is treated by hydroforming a tubular metal patch whose initial diameter is considerably smaller than the well or pipe, particularly for repair and / or plugging purposes, and has the following steps Method:
Inserting the tool (1) with the mandrel (2) axially into the patch (4), where the mandrel (2) has two expansions that can be expanded radially by the action of internal fluid pressure Possible packers (3) are mounted, these two packers (3) being axially spaced from each other at a distance that is substantially the same or slightly shorter than the length of the patch;
Placing the tool (1) inside the patch so that the packer (3) matches the edge (5) of the patch;
Inserting the assembly consisting of the tool (1) and the patch (4) axially into the well or pipe and arranging the assembly to coincide with the area (Z) to be repaired;
The packer (3) is sufficient to cause the two ends (5) of the patch to expand radially and cause it to be pressed against the inner wall of the well or pipe without leaking Inflating with high pressure; and • retracting the packer (3) and extracting the tool (1) from the well or pipe.   For the purpose of pressing the two ends (5) of the patch (4) at least partially after the packer (3) has expanded, so as not to leak against the inner wall of the well or pipe, A pressurized second fluid is introduced inside the patch between the two packers (3), so that the central part (40) of the patch located between the two ends (5) is also hydrotreated. 2. A method according to claim 1, characterized in that the expansion is effected radially by forming, wherein the expansion pressure of the packer (3) is substantially greater than the pressure of the second fluid. 3. The method according to claim 2, wherein the method is executed in a plurality of stages, and each stage further includes the following two stages:
a) In the first stage, the end (5) is partially expanded in the radial direction so that the pressure directly acting on increasing the end diameter to the desired value reaches a predetermined value. By inflating (3), a defined increase in diameter at the end is obtained; and b) In the second stage, the remaining part of the patch is partially expanded radially, ie the patch The central portion (40) of the tube is expanded by hydroforming under the action of a smaller pressure, chosen to obtain an increase in diameter to a predetermined value;
Here, this operation is repeated one or more times until the desired expansion radius in the central part of the patch is reached, and finally the end (5) is expanded to the final value, so that the well Alternatively, the end portion is pressed against the inner wall of the pipe so as not to leak.   When the tool (1) has been placed inside the patch (4), the packer (3) is slightly inflated to fix the tool against the patch (4) by friction. Item 4. The method according to any one of Items 1 to 3.   At least one sensor (100) is installed between the central portion (40) of the patch and the inner wall of the well or pipe, and the sensor (100) is secured to the outside of the central portion (40) of the patch prior to work. The method according to claim 1, wherein: A device for repairing a well or pipe, for example a casing (C), comprising:
The well or pipe has a part (Z) to be treated by hydroforming a tubular metal patch whose initial diameter is considerably smaller than the well or pipe, in particular to be repaired and / or plugged. The device first comprises a tool (1) suitable for being inserted axially into the patch (4), the tool (1) being radially acted upon by the internal fluid pressure. Two expandable packers (3) that can be expanded comprise a mandrel (2) mounted thereon, the two packers (3) having a radius less than the inner diameter of the patch in the contracted state, and Are spaced apart from each other in the axial direction by a distance substantially equal to or slightly shorter than the length so that the tool (1) is positioned with the packer (3) in alignment with the end (5) of the patch Composed Secondly, the assembly consisting of the tool (1) and the patch (4) is inserted axially into the well or pipe so that the assembly coincides with the area (Z) to be repaired. After being placed, the packer (3) causes the two ends (5) of the patch to radially expand and be pressed against the inner wall of the well or pipe so as not to leak. An apparatus comprising fluid pressure means for inflating the packer (3) at a sufficiently high pressure.   The tool (1) includes an axial tube (6) suitable for selective connection to a high pressure fluid pressure source or a low pressure source, which tube (6) opens into the packer (3). 7. Device according to claim 6, characterized in that it has supply and suction holes (61).   The tool (1) is provided with an additional tube or flow path (7, 70) suitable for being connected to a high pressure fluid pressure source, outside the tool mandrel (2) between the packers (3). 8. Device according to claim 6 or 7, characterized in that it has an opening for supply (70).   A cylindrical metal patch (4) suitable for use with the device according to any of claims 6 to 8.   10. A patch according to claim 9, characterized in that its ends (5) are mechanically reinforced and their thickness is greater than the thickness of the central part (40) of the patch.   11. Patch according to claim 9 or 10, characterized in that it acts as a hoop and is reinforced at its end (5) by an outer ring (51) fitted on its wall surface (41).   The end (5) is characterized in that it comprises an outer ring (52), for example made of natural or synthetic rubber, suitable for improving the sealing performance when in contact with the inner wall of a well or pipe. The patch according to any one of 9 to 11.   13. Patch according to claim 12, characterized in that the jacket (52) is made of an expansible material suitable for expanding when in contact with a liquid, in particular water or oil.   The central portion (81) located between the ends (80) has a wall folded in the longitudinal direction, and the undulations (9) of the wall are expanded by the effect of internal pressure, so that the radial expansion of the patch The patch according to claim 9, wherein the patch is promoted.   A method according to any one of claims 9 to 14 for carrying out the method according to claim 5, characterized in that it comprises at least one sensor (100) fixed to the outside of the wall in the central part (8) of the patch. Patch described in.   The patch according to claim 15, wherein the sensor (100) is received in a setback in the wall (400) of the central portion (40).

Images